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Published Date: 2011-04-20 02:50:57
Subject: PRO/AH> White nose syndrome, bats - North America (02): (USA, Canada)
Archive Number: 20110420.1229

WHITE NOSE SYNDROME, BATS - NORTH AMERICA (02): (USA, CANADA)
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A ProMED-mail post
http://www.promedmail.org
ProMED-mail is a program of the
International Society for Infectious Diseases
http://www.isid.org

In this posting:
[1] USA (Maryland)
[2] USA (West Virginia)
[3] Canada (Nova Scotia)

******
[1] USA (Maryland)
Date: Fri 15 Apr 2011
Source: Cumberland Times-News [edited]
http://times-news.com/local/x325992390/Deadly-bat-disease-found-in-Garrett-cave

Deadly bat disease found in Garrett cave
----------------------------------------
Maryland Department of Natural Resources [DNR] biologists have
confirmed that white nose syndrome has been found in a cave in Garrett
County, the 3rd documented case of the disease in Maryland.

The cave serves as an important winter shelter or hibernaculum for
hundreds of bats. The disease has caused unprecedented bat mortality
across the eastern US. Affected bats display a white fungus on their
muzzles or other exposed skin.

"This is the 2nd new infected site we've documented this year
[2011]," said Dan Feller, DNR's Western Region ecologist. "We now have
positive sites in all 3 Maryland counties with bat hibernacula."

A survey by volunteer biologists from Frostburg State University,
working under the direction of DNR, discovered the newly infected
population. 3 little brown bats and one tricolored bat submitted to
the US Geological Survey National Wildlife Health Center tested
positive for the disease. At an infected site discovered last year
[2010] in Allegany County, virtually all of the bats were dead, a
level of devastation similar to other affected sites in the north
east. The disease was found in Washington County last month [March
2011].

"We're relieved that our surveys found several important hibernating
sites still unaffected, including one of the largest populations of
eastern small-footed bats remaining in the United States," said
Feller. "But with the spread of this disease having been fast and
unrelenting, the future of these sites is uncertain."

The disease has spread across mines and caves in 14 states and 2
Canadian provinces, killing more than a million bats. It was first
observed at Howe Cave near Albany, New York, in 2006. It is caused by
a newly discovered cold-weather fungus, _Geomyces destructans_.

Under the direction of the US Fish and Wildlife Service, an
international, interagency team is mobilizing to slow the spread and
find a cure to the disease. It has been shown that bats can transmit
the fungus to each other. And although the disease is not harmful to
people, it may be possible for cavers to spread the fungus through
gear and clothing. State and federal wildlife authorities have asked
that people not enter caves. DNR biologists and volunteers
investigating the disease follow strict decontamination protocols when
working in caves and other bat hibernacula.

Recent research conservatively estimates the value of bats to the US
agricultural industry to be USD 3.7 billion because they eat
agricultural pests. Their value to ecology is more complex and harder
to measure. "This level of devastation to our bats is unprecedented
and tragic," said Tim Larney, habitat conservation program manager for
DNR's Wildlife and Heritage Service. "And it comes at a time when new
research indicates that we may have been underestimating the
importance of bats in keeping ecosystems healthy and productive."

For additional information on white nose syndrome, visit
http://dnr.maryland.gov/wildlife/plants_wildlife/bats/nhpbatdisease.asp.

--
communicated by:
HealthMap Alerts via ProMED-mail
<promed@promedmail.org>

[The state of Maryland can be located on the HealthMap/ProMED-mail
interactive map at http://healthmap.org/r/0IVH. - Sr.Tech.Ed.MJ]

******
[2] USA (West Virginia)
Date: Mon 18 Apr 2011
Source: Beaumont Enterprise, Associated Press (AP) report [edited]
http://www.beaumontenterprise.com/default/article/Fatal-bat-fungus-found-in-W-Va-s-New-River-Gorge-1341847.php

Fatal bat fungus found in West Virginia's New River Gorge
---------------------------------------------------------
Scientists have confirmed the presence of deadly white nose syndrome
among bats at the New River Gorge National River, the US Fish and
Wildlife Service said Monday [18 Apr 2011].

Biologist Mark Graham saw little brown bats flying out of abandoned
mine portals in the Fayette County park in the middle of the day this
past winter [2010-11].

"It was the wrong time of year and definitely the wrong time of day
for healthy bats to be coming out of the mines rather than
hibernating," he said.

Tests later confirmed the disease, which is caused by a fungus and is
blamed for killing more than a million bats in eastern North America.

White nose syndrome, named for the visible fungal growth on bats'
muzzles, ears, and wing membranes, was discovered in a New York cave
in February 2006. It has since spread west into Oklahoma, north into
Canada, and south to North Carolina.

The fungus thrives in cold and humid conditions such as those found
in caves and mines. Scientists, however, are cautious about applying
fungicide in caves or mines for fear of disrupting delicate
subterranean ecosystems. Biologists say 7 of the New River Gorge
park's 10 species hibernate in caves. The other 3 are tree bat
species. 6 of the park's cave-dwelling species, including the
federally endangered Indiana bat, have already proven to be
susceptible to the disease elsewhere in the United States.

The state Division of Natural Resources confirmed the presence of
white nose syndrome last winter in counties just east of the park and
elsewhere in West Virginia.

--
communicated by:
HealthMap Alerts via ProMED-mail
<promed@promedmail.org>

[The state of West Virginia can be located on the
HealthMap/ProMED-mail interactive map at
http://healthmap.org/r/0IVI. - Sr.Tech.Ed.MJ]

******
[3] Canada (Nova Scotia)
Date: Mon 18 Apr 2011 [2011]
Source: Canada Views.ca, Government of Nova Scotia report [edited]
http://www.canadaviews.ca/2011/04/18/early-signs-of-white-nose-syndrome-spreading-to-bats/

Early signs of white nose syndrome spreading to bats
----------------------------------------------------
Nova Scotians are being asked to help slow the spread of a lethal bat
disease, called white nose syndrome, that has been detected in the
little brown bat population in the province. "Although there is no
health risk to people, we are encouraging people to stay out of caves
and old mine workings that are home to bats to limit opportunities for
cross-contamination," said natural resources minister Charlie Parker.

Nova Scotia is the 4th province to discover the fungus, known as
_Geomyces destructans_, which leaves a white ring around a bat's nose,
ears, or wings. A bat flying around in daylight near Brooklyn, Hants
County, on 23 Mar 2011 tested positive. The diagnosis was made at the
Canadian Co-Operative Wildlife Health Centre in Prince Edward Island.

The disease was first confirmed in New York state in 2006, and spread
across the north eastern states into Ontario and Quebec during the
past 2 years. It was also discovered in New Brunswick last month
[March 2011].

"It is necessary to implement measures to control the spread of the
fungal spores associated with the spread of white nose syndrome," said
Natural Resources biologist, Mark Elderkin.

"Our focus now is to better understand the geographic extent of bats
carrying the fungus, while carefully monitoring over-wintering
sites."

Insect-eating bats are crucial to a healthy ecosystem by helping to
control pests, including the spruce budworm, that are destructive to
the forestry and agriculture sectors.

The Department of Natural Resources is asking people to report
sightings of day-flying bats and other unusual behavior to a local
office. Where possible, people should also avoid handling bats.

--
communicated by:
ProMED-mail rapporteur Mary Marshall

[The province of Nova Scotia can be located on the
HealthMap/ProMED-mail interactive map at
http://healthmap.org/r/00EX. - Sr.Tech.Ed.MJ]

[It seemed to take a long time to identify the fungus affecting the
bats and now it seems to be taking a long time to find a
treatment/cure. It only seems a long time to those of us anxiously
waiting a treatment/cure to what seems to be a horrible disease with
devastating effects on the bats.

White nose syndrome (WNS) was named for the visible presence of a
white fungus around the muzzles, ears, and wing membranes of affected
bats. Based upon what is known about typical fungal pathogens of
typical mammals, this fungal growth was initially thought to be a
secondary infection of bats with compromised immune systems. However,
bats are anything but "typical" mammals (see below).

Since then, a previously unreported species of cold loving fungus
(_Geomyces destructans_) has been identified as a consistent pathogen
among affected animals and sites. This fungus, now widely considered
to be the causal agent of WNS, thrives in the darkness, low
temperatures (5-10 deg C; 40-50 deg F), and high levels of humidity
(greater than 90 per cent) characteristic of bat hibernacula. Unlike
typical fungi, _G. destructans_ cannot grow above 20 deg C (68 deg F),
and therefore appears to be exquisitely adapted to persist in caves
and mines and to colonize the skin of hibernating bats. A consistent
pattern of fungal skin penetration has been observed in more than 90
per cent of bats from the WNS-affected region that were submitted for
disease investigation.

White nose syndrome was first documented in a cave that is visited by
tens of thousands of tourists each year, and the disease has since
spread outward from that site. The focal area of origin and subsequent
distribution of affected sites indicate that _G. destructans_ could be
an exotic species with the capacity to spread rapidly among
populations of hibernating bats.

Researchers in Europe have long noticed similar fungal growth on the
faces, ears, and wings of hibernating bats in Europe, but observed no
associated mortality. Work is currently under way to assess whether
there is any connection between fungi seen on bats in North America
and Europe. Recent efforts by researchers in Europe have revealed that
_G. destructans_ occurs on hibernating bats in several countries of
that continent. An alternative hypothesis for the origin of white nose
syndrome is that this fungus was already present in North America, yet
recently mutated to become an emerging disease.

Pathologic findings thus far indicate that bats affected by white
nose syndrome are infected by _G. destructans_, and many appear to
prematurely run out of the stored body fat that they rely on for
winter survival. Species of bats occurring at the higher latitudes of
the world rely on insects for food, which disappear from those
temperate zones during winter. Most species of temperate zone bats
survive the winter by building up fat reserves during autumn and then
going to cold places to hibernate and wait out the winter insect
shortage. During hibernation, a bat slows down its metabolism so that
its body temperature remains just a few degrees above air temperature.
This strategy allows a bat to consume very little fat over winter.
Bats could easily last several months in this deep state of torpor,
but they need to warm their bodies up a few times each winter and
arouse from hibernation so that they can drink, urinate, mate,
relocate, and probably induce their immune systems to catch up. These
natural arousals from hibernation consume a lot of energy, and about
90 per cent of a hibernating bat's winter fat is burned to fuel
natural arousals. If anything increases the frequency or duration of
such arousals during winter, the energy balance of a hibernating bat
can quickly tip toward starvation.

Chronic disturbance of hibernating bats is known to cause abnormal
arousal patterns, and can result in high rates of winter mortality.
For example, certain inappropriate research methods (such as, poorly
applied wing bands and frequent winter visitations) directed toward
hibernating bats in the 1950s and 1960s caused chronic disturbance
that led to high mortality and population declines in several US bat
species (Ellison 2008). Unlike typical microbial pathogens that cause
collapse of internal organ systems, the skin infection caused by _G.
destructans_ may act as a chronic disturbance during hibernation, and
fungal-associated aberrant behaviors likely cause bats to consume
critical body reserves too quickly during winter.

In addition to disrupting hibernation cycles and prematurely
expending energy reserves, it is likely that affected bats suffer
other serious physiological problems (such as dehydration) associated
with the fungus infecting the proportionally huge skin surfaces of
their wings during hibernation.

The newly identified cold-loving fungus is now thought to be the
primary causative agent of white nose syndrome. Available evidence
suggests the fungus establishes itself in the skin tissues of bats
when their body temperatures are lowered during torpor (2-10 deg C;
35-50 deg F). Although life-threatening cutaneous fungal infections of
this sort are rare in warm-blooded birds and mammals, they occur more
frequently in "cold-blooded" animals (such as chytridiomycosis in
amphibians, and crayfish plague). The cold-loving fungus seems to be
infecting bats when they reduce their body temperatures during
hibernation to levels characteristic of "cold-blooded" animals. Fungal
infiltration of the wing membranes of bats may be particularly
problematic. Wing membranes represent about 85 per cent of a bat's
total surface area and play a critical role in balancing complex
physiological processes. Healthy wing membranes are vital to bats, as
they help regulate body temperature, blood pressure, water balance,
and gas exchange -- not to mention the ability to fly and to feed.

Although white nose syndrome was named after the obvious sign of
white noses on affected bats, bat wings may indeed be the most
vulnerable point of infection.

Because the newly identified fungus represents a potential biological
invasion or emerging disease, with severe implications for hibernating
bats in North America, it is important to focus on the history of its
geographic distribution in the context of the distributions of
affected species and those of federal concern that are potentially in
harm's way. Although the true potential for this fungus to spread is
unknown, the possibility of it undermining the ubiquitous survival
strategy of bats at higher latitudes has enormous implications. We are
just beginning to appreciate the roles that bats play in North
American ecosystems, and it is clear that threats like white nose
syndrome have the potential to influence ecosystem function in ways
that we currently do not understand.

Since white nose syndrome emerged during the winter of 2006-2007, a
diverse group of scientists, resource managers, and conservation
groups have worked diligently to establish its cause. Efforts are now
being directed toward developing solutions to the WNS crisis and
minimizing its impact on populations of hibernating bats in North
America.

Portions of this comment have been extracted from
http://www.fort.usgs.gov/WNS/. An excellent map demonstrating the
spread of this disease since winter 2005-06 can also be found at this
site.

Photos
Little brown bat (_Myotis lucifugus_):
http://www.kollewin.com/blog/little-brown-bat_7435/
Indiana bat (_Myotis sodalis_):
http://animal.discovery.com/guides/endangered/mammals/indiana-bat.html
Tri-colored bat (_Perimyotis subflavus_):
http://www.flickr.com/photos/jboyles/3469105946/
Big brown bat (_Eptesicus fuscus_):
http://www.fcps.edu/islandcreekes/ecology/big_brown_bat.htm
Long-eared bat (_Pletocus auritus_):
http://www.naturephoto-cz.com/long-eared-bat:pletocus-auritus-photo-3033.html
WNS on bats:
http://www.austinpost.org/files/articles/bats.jpg. - Mod.TG]

See Also